1. Field of the Invention
The present invention relates to a structure for mounting a multi-optical axis photoelectric sensor on a base of a machine tool or the like, and particularly to a structure for mounting a multi-optical axis photoelectric sensor, where a multi-optical axis photoelectric sensor can be mounted from the front face thereof and a mounting space can be reduced.
2. Description of the Related Art
In recent years, a multi-optical axis photoelectric sensor is in frequent use for a machine tool or the like for monitoring intrusion into a danger area. In the case of mounting such a multi-optical axis photoelectric sensor, it is necessary to position a light projector and a light receiver to be mutually opposed so that the light receiver can receive a light ray projected from a light projector. Hence it is necessary that in the structure for mounting a multi-optical axis photoelectric sensor, the orientation of the sensor can be adjusted.
Therefore, amounting structure has been developed, where a rotating axis is provided at the end of the multi-optical axis photoelectric sensor to adjust the orientation of the sensor. However, since the photoelectric sensor cannot be mounted on amounting structure portion, a dead space is unfavorably created at each end of the multi-optical axis photoelectric sensor. Further, although it is necessary to arrange a plurality of multi-optical axis photoelectric sensors in the case where a mounting place requires a large light curtain, when the multi-optical axis photoelectric sensors are arranged in a line, an aperture in the light curtain is unfavorably created in the mounting structure part. Therefore, a mounting structure has been developed, where a position of a rotation angle of the multi-optical axis photoelectric sensor is adjustable with the use of a mounting device provided on the back face of the multi-optical axis photoelectric sensor (e.g. Japanese Patent Laid-Open No. 2003-242868).
However, since the mounting device 10 grips the side face Ab and the back face Aa of the multi-optical axis photoelectric sensor A, a portion of a base, for mounting a multi-optical axis photoelectric sensor, needs a space for the mounting device 10 in addition to the space for the multi-optical axis photoelectric sensor. There has thus been a problem in that, when the mounting portion is small, the mounting device 10 cannot be used.